The most important compliance factors for ornamental aluminum fence are:

Fence must be at least 48″ (4 ft) tall

The mid-rail must be at least 45″ above the bottom rail.

The spacing between pickets must be less than 4″

The space between the bottom rail and the ground must be less than 4″.

Gates must be self-closing, self-latching, and open outward (away from the pool area).

The opening mechanism of the latch must be at least 54″ above ground.

“Flush” is when the bottom rail encloses the bottom of the pickets, so no pickets are exposed.“Modified” is when the bottom rail has been moved down to meet code, leaving the bottom of the pickets exposed.
Always check local code before ordering and installing pool fencing.